update to sbt and support MAC OSX

Author: shawnZuo

build.sbt

@@ -0,0 +1,13 @@
+
+name := "grazScala"
+
+version := "0.1"
+
+scalaVersion := "2.12.8"
+
+enablePlugins(JavaAppPackaging)
+
+libraryDependencies ++= Seq(
+  "org.scalatest" %% "scalatest" % "3.0.5",
+  "org.apache.commons" % "commons-lang3" % "3.5"
+)

pom.xml

@@ -0,0 +1 @@
+sbt.version = 1.2.8

project/build.properties

@@ -0,0 +1 @@
+addSbtPlugin("com.typesafe.sbt" % "sbt-native-packager" % "1.3.4")

project/plugins.sbt

@@ -3,15 +3,22 @@ package com.liangdp.graphviz4s
 import org.apache.commons.lang3.SystemUtils
 
 /**
- * @author Depeng Liang
- */
+  * @author Depeng Liang
+  */
 object Backend {
 
   // http://www.graphviz.org/cgi-bin/man?dot
   private val ENGINES = Set(
     "dot", "neato", "twopi", "circo", "fdp", "sfdp", "patchwork", "osage"
   )
 
+  val ENGINGSEXECPATH: Map[String, String] = ENGINES.foldLeft(Map[String, String]())({
+    (m, st) => {
+      import sys.process._
+      Map[String, String](st -> s"which $st".!!) ++ m
+    }
+  })
+
   // http://www.graphviz.org/doc/info/output.html
   private val FORMATS = Set(
     "bmp",
@@ -52,61 +59,74 @@ object Backend {
     "x11"
   )
 
-  require(SystemUtils.IS_OS_LINUX, "only support linux right now.")
+  /**
+    * Return command for open a file for default
+    */
+  def viewFileCommand(): String = {
+    if (SystemUtils.IS_OS_LINUX) {
+      "xdg-open"
+    }
+    else if (SystemUtils.IS_OS_MAC || SystemUtils.IS_OS_MAC_OSX) {
+      "open"
+    }
+    else throw new RuntimeException("only support mac OSX or Linux ")
+  }
 
   /**
-   * Return command for execution and name of the rendered file.
-   *
-   * @param engine The layout commmand used for rendering ('dot', 'neato', ...).
-   * @param format The output format used for rendering ('pdf', 'png', ...).
-   * @param filePath The output path of the source file.
-   * @return render command to execute.
-   * @return rendered file path.
-   */
+    * Return command for execution and name of the rendered file.
+    *
+    * @param engine   The layout commmand used for rendering ('dot', 'neato', ...).
+    * @param format   The output format used for rendering ('pdf', 'png', ...).
+    * @param filePath The output path of the source file.
+    * @return render command to execute.
+    */
   def command(engine: String, format: String, filePath: String = null): (String, String) = {
     require(ENGINES.contains(engine) == true, s"unknown engine: $engine")
     require(FORMATS.contains(format) == true, s"unknown format: $format")
     Option(filePath) match {
-      case Some(path) => (s"$engine -T$format -O $path", s"$path.$format")
+      case Some(path) => (s"${ENGINGSEXECPATH(engine)} -T$format -O $path", s"$path.$format")
       case None => (s"$engine -T$format", null)
     }
   }
 
   /**
-   * Render file with Graphviz engine into format,  return result filename.
-   *
-   * @param engine The layout commmand used for rendering ('dot', 'neato', ...).
-   * @param format The output format used for rendering ('pdf', 'png', ...).
-   * @param filepath Path to the DOT source file to render.
-   */
+    * Render file with Graphviz engine into format,  return result filename.
+    *
+    * @param engine   The layout commmand used for rendering ('dot', 'neato', ...).
+    * @param format   The output format used for rendering ('pdf', 'png', ...).
+    * @param filePath Path to the DOT source file to render.
+    */
   @throws(classOf[RuntimeException])
   def render(engine: String = "dot", format: String = "pdf",
-      filePath: String): String = {
+             filePath: String): String = {
     val (args, rendered) = command(engine, format, filePath)
     import sys.process._
     try {
       args !
-    } catch { case _ : Throwable =>
-      val errorMsg = s"""failed to execute "$args", """ +
-      """"make sure the Graphviz executables are on your systems' path"""
-      throw new RuntimeException(errorMsg)
+    } catch {
+      case _: Throwable =>
+        val errorMsg =
+          s"""failed to execute "$args", """ +
+            """"make sure the Graphviz executables are on your systems' path"""
+        throw new RuntimeException(errorMsg)
     }
     rendered
   }
 
   /**
-   * Open filepath with its default viewing application (platform-specific).
-   * For know only support linux.
-   */
+    * Open filepath with its default viewing application (platform-specific).
+    * For know only support linux.
+    */
   @throws(classOf[RuntimeException])
   def view(filePath: String): Unit = {
-    val command = s"xdg-open $filePath"
+    val command = s"$viewFileCommand $filePath"
     import sys.process._
     try {
       command !
-    } catch { case _ : Throwable =>
-      val errorMsg = s"failed to execute $command"
-      throw new RuntimeException(errorMsg)
+    } catch {
+      case _: Throwable =>
+        val errorMsg = s"failed to execute $command"
+        throw new RuntimeException(errorMsg)
     }
   }
 }

src/main/scala/com/liangdp/graphviz4s/Backend.scala

@@ -4,7 +4,7 @@ import java.io.File
 import java.io.PrintWriter
 import scala.collection.mutable.ArrayBuffer
 import scala.collection.mutable.Map
-
+import com.liangdp.graphviz4s.Backend.viewFileCommand;
 /**
  * Assemble, save, and render DOT source code, open result in viewer.
  * @author Depeng Liang
@@ -213,10 +213,13 @@ abstract class Dot(
    */
   protected def _view(filePath: String, format: String): Unit = {
     import sys.process._
+    var command = viewFileCommand
     try {
-      s"xdg-open $filePath" !
+      s"$command $filePath" !
     } catch { case _ : Throwable =>
-      val errorMsg = s"""no built-in viewer support for $format on Linux platform"""
+      val errorMsg =
+        s"""no built-in viewer support for $command $format
+           |on Linux platform""".stripMargin
       throw new RuntimeException(errorMsg)
     }
   }